WASHINGTON — The Obama administration is considering new rules on the design of automobiles, including possible requirements that cars be equipped with advanced-brake technology and "black boxes" that record crash data, the top U.S. highway-safety regulator said. David Strickland, chief of the Transportation Department's National Highway Traffic Safety Administration, made his remarks at a U.S. House hearing during which he defended his agency's response to safety problems involving Toyota Motor Corp., The Wall Street Journal reported. "We have been a very active agency" in responding to the Toyota recalls, Strickland told a House Energy and Commerce subcommittee, calling criticism of the agency "not valid at all." He pointed out that the agency has opened multiple investigations into Toyota. "A lapdog doesn't open any investigations," he said, apparently referring to a criticism leveled by former NHTSA administrator Joan Claybrook, who also testified. Strickland, a former congressional staffer who took the helm of NHTSA in January, said auto-safety regulators are performing a broad review of vehicle designs, including engine electronic systems, to determine whether design standards need to be updated. Under consideration are new rules to upgrade accelerator-pedal design and brakes. In written testimony he submitted to the committee, Strickland said the administration is prepared to require that all cars be equipped with brake-override systems, which are designed to ensure that a car stops if both the gas and brake pedals are depressed. "If our review indicates that requiring this feature could substantially reduce the most dangerous kinds of sudden acceleration, we will strongly consider a rulemaking to require it," he said. Strickland also said the administration is studying whether to require that all vehicles be equipped with event-data recorders, also known as black boxes. Many U.S. vehicles already have the black boxes, while some also are equipped with brake-override systems.